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1.
Bratisl Lek Listy ; 122(12): 912-917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34904854

RESUMO

OBJECTIVES: This study aimed to investigate the wound healing activity of liposomal Carpobrotus edulis powder extract (CEPE) formulation on incisional and excisional wounds in rat. BACKGROUND: In the event of any damage, the damaged tissue undergoes a process of regenerating itself, which is called wound healing. METHODS: Centella asiatica extract (CAE) was used as the reference molecule in the study. The wound healing process was tested by using the excisional and incisional wound model. On the 12th day of the study, maximum stress, stress, % of elongation values were evaluated in the incisional wound. Also; histological parameters and macroscopic photographic analyses were evaluated in the excisional wound. RESULTS: In the photo evaluations, the improvement was more prominent in both CAE and CEPE groups than in the control group. Histological evaluation showed that CEPE group had significant wound healing activity compared to the control and CAE groups. Axial tensile-elongation experiments in incisional wound tissue show that there was no significant difference between CAE and CEPE groups. CONCLUSION: Liposomal formulations of C.edulis extract were found to have positive effects on the healing process, both on excisional and incisional wound tissues (Tab. 2, Fig. 3, Ref. 30).


Assuntos
Pele , Cicatrização , Animais , Extratos Vegetais/farmacologia , Ratos
2.
Transgenic Res ; 25(5): 597-607, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27339146

RESUMO

Experience gained in the risk assessment (RA) of genetically engineered (GE) crops since their first experimental introductions in the early nineties, has increased the level of familiarity with these breeding methodologies and has motivated several agencies and expert groups worldwide to revisit the scientific criteria underlying the RA process. Along these lines, the need to engage in a scientific discussion for the case of GE crops transformed with similar constructs was recently identified in Argentina. In response to this need, the Argentine branch of the International Life Sciences Institute (ILSI Argentina) convened a tripartite working group to discuss a science-based evaluation approach for transformation events developed with genetic constructs which are identical or similar to those used in previously evaluated or approved GE crops. This discussion considered new transformation events within the same or different species and covered both environmental and food safety aspects. A construct similarity concept was defined, considering the biological function of the introduced genes. Factors like environmental and dietary exposure, familiarity with both the crop and the trait as well as the crop biology, were identified as key to inform a construct-based RA process.


Assuntos
Produtos Agrícolas/genética , Alimentos Geneticamente Modificados/normas , Engenharia Genética/normas , Plantas Geneticamente Modificadas , Argentina , Cruzamento , Qualidade de Produtos para o Consumidor/normas , Medição de Risco
3.
Nature ; 460(7258): 990-4, 2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19693079

RESUMO

A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz.

4.
Phys Rev Lett ; 107(27): 271102, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22243300

RESUMO

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2) Hz(-1) and 5-35×10(-49) strain(2) Hz(-1) sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.

5.
Appl Opt ; 49(25): 4780-90, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20842804

RESUMO

In-vacuum Faraday isolators (FIs) are used in gravitational wave interferometers to prevent the disturbance caused by light reflected back to the input port from the interferometer itself. The efficiency of the optical isolation is becoming more critical with the increase of laser input power. An in-vacuum FI, used in a gravitational wave experiment (Virgo), has a 20 mm clear aperture and is illuminated by an almost 20 W incoming beam, having a diameter of about 5 mm. When going in vacuum at 10(-6) mbar, a degradation of the isolation exceeding 10 dB was observed. A remotely controlled system using a motorized lambda=2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air.

6.
Prikl Biokhim Mikrobiol ; 15(6): 822-6, 1979.
Artigo em Russo | MEDLINE | ID: mdl-395534

RESUMO

The effect of dehydration on the fatty acid composition of lipids in baker's yeast Saccharomyces cerevisiae 14 cultivated on the ethanol (1.5%) containing medium in the presence or absence of glutamic acid and biotin or on molasses (2%) was studied. In spite of a relatively low drying temperature (35 degrees C), the correlation between saturated and non-saturated fatty acids may vary within 40--60 min.


Assuntos
Ácidos Graxos/análise , Metabolismo dos Lipídeos , Saccharomyces cerevisiae/metabolismo , Biotina/farmacologia , Glutamatos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Relação Estrutura-Atividade
7.
Prikl Biokhim Mikrobiol ; 13(6): 893-900, 1977.
Artigo em Russo | MEDLINE | ID: mdl-341116

RESUMO

Essential redistribution of various polyphosphate fractions was shown during dehydration and subsequent reactivation of Saccharomyces cerevisiae 14. Dehydration no matter what method was used, was followed by an increase in the content of acid soluble polyphosphates (fraction Poly P1) and a decrease of that of salt soluble polyphosphates (fraction Poly P2). Reactivation of dehydrated yeast was, on the contrary, accompanied by a decrease in the PP 1 and an increase in the Poly P2 content. A direct correlation between the Poly P2 fraction and total nucleic acids was demonstrated under various conditions of dehydration and subsequent reactivation. An inverse correlation between the content of the Poly P2, fraction and nucleic acids, on the one hand, and that of the Poly P1 fraction, on the other, was observed. Study of activities of polyphosphatases, tripolyphosphatase, pyrophosphatase and ATPase in dehydrated yeast showed values similar to those in original cells.


Assuntos
DNA/metabolismo , Polifosfatos/metabolismo , RNA/metabolismo , Saccharomyces cerevisiae/metabolismo , Dessecação
8.
Rev Sci Instrum ; 85(3): 034501, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24689604

RESUMO

There is a strong scientific case for the study of gravitational waves at or below the lower end of current detection bands. To take advantage of this scientific benefit, future generations of ground based gravitational wave detectors will need to expand the limit of their detection bands towards lower frequencies. Seismic motion presents a major challenge at these frequencies and vibration isolation systems will play a crucial role in achieving the desired low-frequency sensitivity. A compact vibration isolation system designed to isolate in-vacuum optical benches for Advanced Virgo will be introduced and measurements on this system are used to present its performance. All high performance isolation systems employ an active feedback control system to reduce the residual motion of their suspended payloads. The development of novel control schemes is needed to improve the performance beyond what is currently feasible. Here, we present a multi-channel feedback approach that is novel to the field. It utilizes a linear quadratic regulator in combination with a Kalman state observer and is shown to provide effective suppression of residual motion of the suspended payload. The application of state observer based feedback control for vibration isolation will be demonstrated with measurement results from the Advanced Virgo optical bench suspension system.

9.
Rev Sci Instrum ; 82(9): 094502, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21974605

RESUMO

We report an application of Kalman filtering to the inverted pendulum (IP) of the Virgo gravitational wave interferometer. Using subspace method system identification techniques, we calculated a linear mechanical model of Virgo IP from experimental transfer functions. We then developed a Kalman filter, based on the obtained state space representation, that estimates from open loop time domain data, the state variables of the system. This allows the observation (and eventually control) of every resonance mode of the IP mechanical structure independently.

11.
Mikrobiologiia ; 47(1): 170-2, 1978.
Artigo em Russo | MEDLINE | ID: mdl-349315

RESUMO

Endocellular acid phosphatase was found to be activated in the course of dehydration of Saccharomyces cerevisiae and at the beginning of its reactivation. This suggests an increase in the number of lysosomes in the cells. Apparently, a damage of the lysosomal membranes may be one of the factors that cause death of yeast cells upon their dehydration.


Assuntos
Fosfatase Ácida/metabolismo , Saccharomyces cerevisiae/enzimologia , Dessecação , Ativação Enzimática , Lisossomos/enzimologia
12.
Mikrobiologiia ; 55(5): 855-7, 1986.
Artigo em Russo | MEDLINE | ID: mdl-3547043

RESUMO

From 26 to 43% of RNA undergoes degradation in yeast cells when they pass into the state of anabiosis. Most of the degradation was found to occur at the first stage of cell dehydration when free water was removed from the cells. The mechanism of RNA degradation is supposed to involve enzyme-catalysed processes which are realised in the cell at the early stages of its dehydration.


Assuntos
Dessecação , RNA Fúngico/metabolismo , Saccharomyces cerevisiae/enzimologia , RNA Fúngico/análise , Saccharomyces cerevisiae/análise , Espectrofotometria , Fatores de Tempo
13.
Mikrobiologiia ; 52(5): 719-22, 1983.
Artigo em Russo | MEDLINE | ID: mdl-6363887

RESUMO

Incubation of Saccharomyces cerevisiae cells in solutions containing different sucrose or lactose concentrations (0.25 to 1.0 M) makes the organism more resistant to dehydration. The effect is increased when the cells are incubated for longer periods of time. Apparently, certain intracellular reactions making the yeast survive upon dehydration are initiated under these conditions.


Assuntos
Dessecação , Lactose/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Sacarose/farmacologia , Relação Dose-Resposta a Droga , Saccharomyces cerevisiae/fisiologia , Fatores de Tempo
14.
Mikrobiologiia ; 51(6): 901-4, 1982.
Artigo em Russo | MEDLINE | ID: mdl-6759885

RESUMO

A considerable quantity of potassium and magnesium ions was found to be released from Saccharomyces cerevisiae cells being in the state of anabiosis upon their rehydration. The nearly maximal (for each of the experiments) quantity of ions was released as early as when cells dehydrated to a residual humidity of ca. 20% were rehydrated. A further decrease of the residual humidity down to 8-10% did not increase the leakage of the ions when the cells were rehydrated. It was concluded that the permeability of the cytoplasmic and vacuolar membranes for the ions increased when the cells were dehydrated and that this phenomenon should be attributed to the removal of free water from the cells.


Assuntos
Permeabilidade da Membrana Celular , Dessecação , Membranas Intracelulares/fisiologia , Saccharomyces cerevisiae/fisiologia , Água/metabolismo , Magnésio/metabolismo , Potássio/metabolismo , Vacúolos/metabolismo
15.
Mikrobiologiia ; 58(4): 679-80, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2695800

RESUMO

The effect of dehydration on the cytoplasmic membrane of yeast cells was studied using the method of spin labels. In the course of dehydration, the thermoinduced transition of lipids from the solid to a liquid-crystalline state was found to occur at a higher temperature as compared with native membranes.


Assuntos
Membrana Celular , Dessecação , Saccharomyces cerevisiae , Temperatura Alta , Lipídeos de Membrana
16.
Biull Eksp Biol Med ; 95(1): 54-6, 1983 Jan.
Artigo em Russo | MEDLINE | ID: mdl-6830961

RESUMO

Study of the immune reactions of the humoral and cellular types in rats, which had suffered terminal condition, has demonstrated the development of sensitization. The degree of the immunological shifts was determined by clinical death duration and by the period of postresuscitation. Injection of piracetam (100 mg/kg, subcutaneously) within the first 10 days after resuscitation noticeably reduced the manifestations of neurosensitization.


Assuntos
Anticorpos/análise , Encéfalo/imunologia , Imunização , Piracetam/administração & dosagem , Pirrolidinonas/administração & dosagem , Ressuscitação , Animais , Formação de Anticorpos/efeitos dos fármacos , Autoantígenos/análise , Morte Súbita , Imunidade Celular/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Formação de Roseta , Baço/imunologia
17.
Mikrobiologiia ; 55(1): 116-9, 1986.
Artigo em Russo | MEDLINE | ID: mdl-3517600

RESUMO

The formation of lipid granules in Saccharomyces cerevisiae cells was shown to begin in the exponential phase of the culture growth and to be associated with the activity of the endoplasmic reticulum. Lipid granules can be formed (1) when the endoplasmic reticulum cisterns extend and (2) when the endoplasmic reticulum membranes separate relatively small regions of the cell cytoplasm. Yeast cells contain spherosomes which differ in their structure. Lipid granules merge together upon dehydration of yeast cells. The authors discuss possible participation of these granules in the reparation of damages of the intracellular membranes.


Assuntos
Metabolismo dos Lipídeos , Saccharomyces cerevisiae/metabolismo , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , Dessecação , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Microscopia Eletrônica , Preservação Biológica , Saccharomyces cerevisiae/ultraestrutura
18.
Mikrobiologiia ; 64(2): 275-8, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7616882

RESUMO

When studying the dehydration effect of the eukaryotic cells on the structural and functional characteristics of the cytoplasmic membrane, it was established that serious rearrangements of its molecular organization showing up in a drastic increase in the permeability properties occurred in the yeast when the range of residual humidities of the order of 20-30% was reached. These changes were linked to the beginning of losing some bound water by the cells. It was shown that these rearrangements were reparable, and the normal membrane structure could be restored in the process of slow and gradual rehydration of dehydrated cells in the water vapors.


Assuntos
Citoplasma/metabolismo , Membranas Intracelulares/fisiologia , Saccharomyces cerevisiae/fisiologia , Adaptação Fisiológica , Citoplasma/ultraestrutura , Permeabilidade
19.
Mikrobiologiia ; 57(3): 491-3, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3054438

RESUMO

The work was concerned with studying the balance of trehalose distribution between the rehydration medium and Saccharomyces cerevisiae cells grown in a chemically defined medium and dehydrated using the convective technique. A direct linear correlation between the viability of populations and the overall residual trehalose content in the cells and in the medium after the rehydration of dry yeast cells was shown to be most important. An inverse correlation was established between the viability of yeast cells and the amount of trehalose mobilised by the cells in the process of rehydration.


Assuntos
Meios de Cultura/metabolismo , Dissacarídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Trealose/metabolismo , Dessecação
20.
Mikrobiologiia ; 50(5): 891-7, 1981.
Artigo em Russo | MEDLINE | ID: mdl-7033736

RESUMO

The release of proteins was studied during rehydration of Saccharomyces cerevisiae cells dehydrated using two techniques which were characterized by different survival rate. A correlation was established between the loss of proteins and the survival rate of cells after dehydration and rehydration. Proteins with a molecular mass from 6000 to 70,000 daltons (low molecular weight proteins predominating) were found in the rehydration medium by the method of disc-electrophoresis in polyacrylamide gel in the presence of sodium dodecylsulfate. Moreover, the rehydration medium exhibited the activity of certain phosphohydrolases and dehydrogenases; this finding suggests that proteins with a higher molecular weight are present in the medium.


Assuntos
Proteínas Fúngicas/metabolismo , Saccharomyces cerevisiae/fisiologia , Dessecação , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/análise , Peso Molecular
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